WO2015064012A1

WO2015064012A1 - Friction stir welding device and method for manufacturing metal structure

Info

Publication number: WO2015064012A1
Application number: PCT/JP2014/005023
Authority: WO
Inventors: 西田　英人; 脩平吉川; 賢一上向; 豪生岡田; 大樹織部
Original assignee: 川崎重工業株式会社
Priority date: 2013-11-01
Filing date: 2014-10-01
Publication date: 2015-05-07
Also published as: JP2015085382A; EP3064306A1; JP6224993B2; CA2926542A1; EP3064306B1; EP3064306A4; BR112016009172B1; US20160263696A1

Abstract

A friction stir welding device (1) equipped with: a rotary tool (2) having at its tip a stirring pin (21); a shoulder (8) into which the rotary tool (2) is inserted; a rotary driving device (41) that causes the rotary tool (2) to rotate around an axis; a pressing device (42) that presses the rotary tool (2) and the shoulder (8) against an inner corner part (90); a moving device (43) that moves the rotary tool (2) and the shoulder (8) along the inner corner part (90) in the direction of travel; and a wire heating device (45) that heats a wire to be friction-stirred with two metal members (members to be bonded (91, 92)) by means of the stirring pin (21).

Description

Friction stir welding apparatus and metal structure manufacturing method

The present invention relates to a friction stir welding apparatus that performs friction stir welding on an inner corner formed by two metal members that are abutted to each other, and a method for manufacturing a metal structure using the friction stir welding apparatus.

Conventionally, friction stir welding (FSW; Friction Stir Welding) is known as a method for joining metal members. In this friction stir welding, the periphery of the welded portion is softened by frictional heat by pressing the stirring pin provided at the tip of the rotary tool against the welded portion of the two metal members while rotating, and the welded portion This is a technique for joining two metal members by stirring and softening the peripheral softened part and cooling the joined part away from the rotating tool.

Patent Document 1 discloses an inner corner rotating tool for performing friction stir welding on inner corners of two metal members which are abutted. The rotary tool includes a stirring pin that is press-fitted into an inner corner formed by two metal members abutted against each other, and a shoulder block that rotatably supports the stirring pin and contacts each of the two metal members. ing. The shoulder block has a main body part, a shoulder part detachably provided on the main body part, and a through hole penetrating the main body part and the shoulder part. When friction stir welding is performed using the inner corner rotating tool, a shoulder block is first installed at the inner corner of the two metal members that are abutted, and then a stirring pin is inserted into the through hole of the shoulder block. Subsequently, the shoulder block and the stirring pin are pressed against the inner corner portion while rotating the stirring pin and moved along the line of the inner corner portion.

Further, in Patent Document 2, a wire is disposed along an inner corner formed by two metal members that are abutted together, and a base material and a wire at the inner corner are combined with an agitator pin to which a shoulder is attached. It describes that the inner corner is friction stir welded by stirring. A fillet is formed in the joined inner corner by the wire that is friction-stirred with the base material of the inner corner.

JP 2011-79031 A JP 2013-166159 A

As described in Patent Document 1 and Patent Document 2, when the shoulder (or shoulder block) does not rotate when friction stir welding is performed on the inner corner formed by the two metal members abutted, Compared with the case where the shoulder rotates together with the stirring pin, the amount of heat input to the bonded portion is reduced. For this reason, particularly when the wire is frictionally stirred together with the base material of the joined portion, the softening of the base material and the wire at the inner corner may be insufficient due to insufficient heat input. In this case, the base metal and the wire in the inner corner are not sufficiently stirred, and there is a possibility that a defect may occur on the surface of the inner corner after joining.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a friction stir welding apparatus that performs friction stir welding to an inner corner formed by two metal members that are abutted together, and the friction stir welding. In the method for manufacturing a metal structure using the apparatus, the wire is supplied to the bonded portion so that the base material of the bonded portion (inner corner) and the wire are frictionally stirred.

The friction stir welding apparatus according to the present invention is a friction stir welding apparatus that performs friction stir welding on an inner corner formed by two metal members that are faced to each other.
A rotating tool having a stirring pin at the tip;
A shoulder inserted through the rotary tool and abutting against the two metal members;
A rotation drive device for rotating the rotating tool around an axis;
A pressing device that presses the rotating tool and shoulder against the inner corner; and
A moving device for moving the rotating tool and the shoulder in the traveling direction along the inner corner;
And a wire heating device that heats the wire that is frictionally stirred together with the two metal members by the stirring pin.

According to the friction stir welding apparatus having the above configuration, the preheated wire is friction stir together with the base material of the joined portion. Therefore, it becomes possible to eliminate the insufficient softening of the base material and the wire of the joined part due to the insufficient heat input to the base material and the wire of the joined part. Moreover, since the base material and the wire of a to-be-joined part are fully softened, the base material and the wire of a to-be-joined part can be friction-stirred favorably. Furthermore, since the amount of heat input necessary for softening the wire is reduced by preheating the wire, the bonding speed can be improved.

The friction stir welding apparatus further includes a wire feeding device that feeds the wire to the joined portion of the two metal members, and the wire heating device feeds the joined portion by the wire feeding device. Preferably, the wire is configured to be heated. According to the said structure, the heated wire can be continuously supplied to a to-be-joined part.

In addition, as the wire heating device, a device configured to heat the wire by energizing the wire can be used. Alternatively, a device configured to heat the wire by electromagnetic induction can be used as the wire heating device. Alternatively, a device configured to heat the wire with a heating element can be used as the wire heating device.

In the friction stir welding apparatus, the shoulder is
An insertion hole through which the rotating tool is inserted;
Two shoulder surfaces provided on both sides in a direction substantially perpendicular to the traveling direction with the opening of the insertion hole interposed therebetween, and forming an angle corresponding to the angle of the inner corner formed by the two metal members; ,
It has a guide groove for the wire that is provided at a front ridge line portion where the two shoulder surfaces intersect in front of the opening direction of the insertion hole and extends in parallel with the moving direction. Good.

According to the above configuration, the wire is guided by the guide groove and supplied to the joined portion. Therefore, the wire is stably supplied to the bonded portion without moving or buckling from the bonded portion.

In the friction stir welding apparatus, the front ridge line part recedes from the inner corner part than the rear ridge line part where the two shoulder surfaces intersect at the rear in the traveling direction from the opening part of the insertion hole, It is preferable that the cross-sectional shape in the advancing direction of the rear ridge line portion has a shape corresponding to the cross-sectional shape in the advancing direction of the inner corner portion after joining. According to the said structure, a wire is supplied to a to-be-joined part, without being inhibited with a shoulder or a base material. And the surface shape of the base material after stirring is arranged because a back ridgeline part and the base material after stirring contact.

In the friction stir welding apparatus, it is preferable that the front ridge line portion is inclined so as to be separated from the inner corner portion toward the front in the traveling direction. Here, the size of the guide groove in the depth direction from one end in the traveling direction of the front ridge line portion to the other end in the traveling direction is preferably larger than the depth of the guide groove. According to the above configuration, the wire can be prevented from being caught by the shoulder.

In the friction stir welding apparatus, the shoulder may be detachably attached, and may further include a base having a hole continuous with the insertion hole of the shoulder. According to the said structure, the shoulder which is comparatively easy to deteriorate can be replaced | exchanged independently from a base.

The method for producing a metal structure according to the present invention includes:
Butting the first metal member and the second metal member into an L shape or a T shape,
Heating the wire;
Supplying the heated wire to an inner corner formed by the butted first metal member and the second metal member;
Press-fitting a stirring pin that rotates into the inner corner, and friction stir welding the first metal member, the second metal member, and the wire.

According to the method for manufacturing a metal structure, the preheated wire is frictionally agitated together with the base material of the bonded portion. Therefore, it becomes possible to eliminate the insufficient softening of the base material and the wire of the joined part due to the insufficient heat input to the base material and the wire of the joined part. Moreover, since the base material and the wire of a to-be-joined part are fully softened, the base material and the wire of a to-be-joined part can be friction-stirred favorably. As a result, it is possible to prevent a defect from occurring on the surface of the friction stir welding portion in the metal structure. Furthermore, since the amount of heat input necessary for softening the wire is reduced by preheating the wire, the bonding speed can be improved.

In heating the wire, for example, the wire can be heated by energizing the wire, the wire can be heated by electromagnetic induction, or the wire can be heated by a heating element.

In the metal structure manufacturing method, for example, the first metal member is made of an A2000 series aluminum alloy, the second metal member is made of an A7000 series aluminum alloy, and the wire is an A2000 series aluminum alloy or an A7000 series aluminum alloy. It may consist of:

According to the present invention, since the preheated wire is supplied to the bonded portion, the base material and the wire of the bonded portion can be appropriately softened by the heat input of the bonded portion by the stirring pin. As a result, the base material and the wire of the joined portion are frictionally stirred.

FIG. 1 is a diagram illustrating a state in which inner corners of two metal members that are abutted are being stirred by a rotating tool. FIG. 2 is a diagram showing a schematic configuration of a friction stir welding apparatus according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the shoulder block in the traveling direction. FIG. 4 is a view of the shoulder as seen from the direction orthogonal to the traveling direction. FIG. 5 is a view taken in the direction of arrow V in FIG. 6 is a view taken along arrow VI in FIG. 7 is a view taken along arrow VII in FIG. FIG. 8 is a view of the shoulder viewed from the traveling direction, showing a modified example of the guide groove of the shoulder. FIG. 9 is a flowchart showing a method for manufacturing a metal structure using a friction stir welding apparatus. FIG. 10 is a diagram illustrating a schematic configuration of a friction stir welding apparatus including a wire heating device according to a modification.

Hereinafter, a friction stir welding apparatus 1 and a metal structure manufacturing method according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a view showing a state in which the inner corner portion 90 of the two

metal members

91 and 92 that are abutted is being stirred by the rotary tool 2. As shown in FIG. 1, the friction stir welding apparatus 1 according to the present embodiment has an inner corner 90 formed by a first member 91 and a second member 92 that are abutted in an L shape or a T shape. It is a device that performs friction stir welding. Using the friction stir welding apparatus 1, a metal structure including the first member 91 and the second member 92 that are friction stir welded can be manufactured.

The first member 91 and the second member 92, which are the members to be joined, may be made of the same metal material as long as it is a metal material (raw material) capable of friction stir welding. May be. When the first member 91 and the second member 92 are made of different metal materials, for example, the first member 91 may be made of an A2000 series aluminum alloy and the second member 92 may be made of an A7000 series aluminum alloy. it can. In this case, it is desirable that the wire 50 friction-stirred with the members to be joined 91 and 92 is made of an A2000 series aluminum alloy or an A7000 series aluminum alloy.

A2000 series aluminum alloy is an aluminum-copper type alloy containing 3.5% or more of copper. The A7000 series aluminum alloy is an aluminum-zinc-magnesium-copper alloy. The A7000 series aluminum alloy has extremely high tensile strength and hardness compared to the A2000 series aluminum alloy, but is inferior to the A2000 series aluminum alloy in terms of fatigue strength and fracture toughness. Therefore, in order to improve the fatigue strength and fracture toughness of the structure, an A2000 series aluminum alloy is disposed on the outer surface of the structure, and the A7000 series aluminum alloy is used in combination in a T shape as an internal reinforcing member. is there. If the friction stir welding of the A2000 series aluminum alloy member and the A7000 series aluminum alloy member is performed using the friction stir welding apparatus 1 according to the present embodiment, these members do not intervene with a connecting member such as a rivet. Since it is joined directly, fatigue strength and fracture toughness are improved, and cost reduction and weight reduction are possible.

Next, the configuration of the friction stir welding apparatus 1 will be described in detail. FIG. 2 is a diagram showing a schematic configuration of the friction stir welding apparatus 1 according to the embodiment of the present invention. In FIG. 2, the shoulder block 3 is shown as a cross-sectional view in a direction orthogonal to the traveling direction 100. FIG. 3 is a cross-sectional view of the shoulder block 3 in the traveling direction. In this figure, the rotary tool 2 is indicated by a two-dot chain line.

As shown in FIGS. 2 and 3, the friction stir welding apparatus 1 according to this embodiment includes a rotary tool 2 having a stirring pin 21 at the tip, a shoulder block 3 attached to the rotary tool 2, and a rotary tool 2. A rotary drive device 41 that rotates the rotary tool 2, a pressing device 42 that presses the rotary tool 2 so that the stirring pin 21 is pressed into the base material of the joined portion with a predetermined pressing force, and a moving device 43 of the rotary tool 2. And a wire feeding device 44, a wire heating device 45, and a control device 46 that controls the operation of the friction stir welding device 1. The members to be joined 91 and 92 are held by a jig 95 as shown in FIG. 1, for example, so that the pressing force from the rotary tool 2 can be received.

The moving device 43 moves the rotary tool 2 and the shoulder block 3 relative to the first member 91 and the second member 92 along the abutting line of the inner corner 90 formed by the first member 91 and the second member 92. It is a means to move to. In this specification, the moving direction of the rotary tool 2 and the shoulder block 3 is referred to as “traveling direction 100”, and the traveling direction 100 is along the butt line of the inner corner 90. In addition, the direction in which the rotary tool 2 and the shoulder block 3 move during machining is referred to as “front” (the direction indicated by the arrow 100 in FIG. 1). 2 and the shoulder block 3 are referred to as “rear”. The rotating tool 2 and the shoulder block 3 move forward to the side where the rotating direction of the rotating tool 2 and the traveling direction 100 coincide with each other, and the rotating tool 2 and the shoulder block 3 move to the side where the rotating direction and the traveling direction 100 are opposite. The shoulder block 3 moves backward.

The moving device 43 can be constituted by, for example, a linear motion guide mechanism and a drive unit of the linear motion guide mechanism controlled by the control device 46 (none of which is shown). However, the moving device 43 may be a robot. The moving device 43 according to the present embodiment moves the rotary tool 2 with respect to the members to be bonded 91 and 92 held by the jig 95, but the moving device 43 holds the members to be bonded 91 and 92. The jig 95 may be moved with respect to the rotary tool 2.

The wire feeding device 44 is a means for feeding the wire 50 to the joined portion in accordance with the joining speed. The wire feeding device 44 includes, for example, a servo motor controlled by the control device 46 and a feeding roller driven by the servo motor (both not shown). In the present embodiment, the wire 50 fed to the bonded portion by the wire feeding device 44 is wound around the wire reel 47 in a coil shape, but the wire 50 is the length of the butting line of the inner corner portion 90. It may be cut according to the size.

The wire heating device 45 is means for heating the wire 50 that is frictionally stirred together with the

members

91 and 92 to be joined. The wire heating device 45 preheats the wire 50 supplied to the bonded portions of the bonded

members

91 and 92. The wire heating device 45 according to the present embodiment is configured to heat the wire 50 fed to the bonded portion by the wire feeding device 44. The wire heating device 45 includes, for example, a contact chip 45a and a wire heating power supply 45b that supplies a current to the contact chip 45a and the base material. The operation of the wire heating power supply 45b is controlled by the control device 46. In the wire heating device 45, a current is supplied from the contact tip 45a to the wire 50 guided to the contact tip 45a. By energizing the wire 50 in this way, the wire 50 is heated by the resistance of the wire 50.

Contact tips 45 a of the wire feeding device 44 and the wire heating device 45 are attached to a stay 33 fixed to the shoulder block 3, and the traveling direction relative to the

members

91 and 92 to be joined with the shoulder block 3. Move to 100. As described above, in order to stably feed the high-temperature wire 50 to the bonded portion, the contact tip 45a of the wire feeding device 44 and the wire heating device 45 is always in a position close to the shoulder block 3 and the rotary tool 2. It is desirable to be present. However, at least one of the wire feeding device 44 and the wire heating device 45 may be provided independently of the shoulder block 3 and the rotary tool 2 at a position away from them.

Here, the shoulder block 3 will be described in detail. 1 to 3, the shoulder block 3 includes a shoulder 8 and a base 7 to which the shoulder 8 is detachably attached. As described above, the shoulder block 3 is divided into the base 7 and the shoulder 8, so that the shoulder 8 that is relatively easily deteriorated can be replaced independently of the base 7. Although not shown, the shoulder block 3 is formed with a cooling hole for cooling the rotary tool 2 and a refrigerant passage through which the refrigerant is conducted.

The base 7 is a hexagonal columnar body whose outer shape viewed from the traveling direction 100 is cut out from two corners adjacent to a rectangle. The surfaces formed by notching two adjacent corners are

guide surfaces

72 and 72. When the shoulder block 3 is pushed into the inner corner 90 by the pressing device 42, shoulder surfaces 85 and 85, which will be described later, come into contact with the

members

91 and 92, but the guide surfaces 72 and 72 are members to be joined. 91 and 92 are spaced slightly apart from each other. The angle formed by the two

guide surfaces

72 and 72 is determined corresponding to the angle of the inner corner portion 90 formed by the members to be joined 91 and 92. In the present embodiment, the angle formed by the two

guide surfaces

72, 72 is about 90 °.

The surface sandwiched between the two guide surfaces 72 is a mounting surface 71 to which the shoulder 8 is mounted. The mounting surface 71 is provided with a recess 73 in which the shoulder 8 is installed. A through hole 74 and a plurality of attachment holes 75 (FIG. 2) are opened in the recess 73. The attachment hole 75 is a hole into which a bolt for fixing the shoulder 8 to the recess 73 is inserted, and a screw is cut on the inner surface.

4 is a view of the shoulder 8 as viewed from a direction orthogonal to the traveling direction 100, FIG. 5 is a view taken along the arrow V in FIG. 4, FIG. 6 is a view taken along the arrow VI in FIG. It is. As shown in FIGS. 4 to 7, the shoulder 8 is integrally formed with a substrate portion 81 fitted into the recess 73 of the base 7 and a protruding portion 82 protruding from the substrate portion 81 toward the inner corner 90. ing.

The substrate portion 81 is provided with an attachment hole 83 corresponding to the attachment hole 75 of the base 7. In a state where the substrate portion 81 of the shoulder 8 is fitted in the recess 73 of the base 7, a continuous bolt hole is formed by the mounting hole 75 of the

base

7 and 83 of the shoulder 8. The shoulder 8 is fixed to the base 7 by inserting a bolt into the bolt hole.

A through hole 84 is opened at the protruding end of the protruding portion 82. The through hole 84 penetrates the substrate portion 81 and the protruding portion 82. In a state where the shoulder 8 is attached to the base 7, one continuous insertion hole 31 is formed by the through hole 74 of the base 7 and the through hole 84 of the shoulder 8.

In the projecting portion 82, shoulder surfaces 85 and 85 are respectively formed on both sides in a direction substantially orthogonal to the traveling direction 100 with the opening of the through hole 84 interposed therebetween. The angle formed by the two

shoulder surfaces

85 and 85 is determined corresponding to the angle of the inner corner portion 90 formed by the members to be joined 91 and 92. In the present embodiment, the angle formed by the two

shoulder surfaces

85, 85 is about 90 °. When the shoulder block 3 is pressed against the inner corner portion 90, the shoulder surfaces 85 and 85 come into contact with the members to be joined 91 and 92 forming the inner corner portion 90.

In the projecting portion 82,

ridge portions

86 and 88 are formed at portions where the two

shoulder surfaces

85 and 85 intersect. The direction in which the ridge lines 86 and 88 extend is parallel to the direction in which the inner corner 90 extends. The ridge line portion penetrates into a front part in the traveling direction 100 (hereinafter referred to as a front ridge line part 86) from the through hole 84 and a rear part (hereinafter referred to as a rear ridge line part 88) in the traveling direction 100 from the through hole 84. It is divided into front and rear with the hole 84 in between.

In the front ridge line portion 86, a guide groove 87 for guiding the wire 50 is formed. The guide groove 87 extends substantially parallel to the traveling direction 100. The cross-sectional shape in the traveling direction 100 of the guide groove 87 according to the present embodiment is a hemisphere. However, the cross-sectional shape in the traveling direction 100 of the guide groove 87 is not limited to a hemisphere. For example, as illustrated in FIG. 8, the cross-sectional shape in the traveling direction 100 of the guide groove 87 is a polygon. Also good.

Conventionally, when a wire is frictionally stirred together with a base material at an inner corner, as described in Patent Document 2, the wire is arranged along the inner corner before stirring. This wire is not supplied stably to the welded part because it receives force while the base metal at the inner corner is frictionally stirred or buckles against peripheral members such as a shoulder. was there. On the other hand, in the friction stir welding apparatus 1 according to the present embodiment, the shoulder 8 has the guide groove 87 of the wire 50, so that even the wire 50 softened somewhat by heating is guided to the guide groove 87. It can be stably supplied to the bonded portion without shaking or buckling in the horizontal direction or the vertical direction.

The front ridge line portion 86 is inclined in a direction away from the inner corner portion 90 toward the front in the traveling direction 100. The inclination of the front ridge line portion 86 is provided from the rear end in the traveling direction 100 of the front ridge line portion 86 to the front end in the traveling direction 100. The inclination of the front ridge line portion 86 is gentle in the vicinity of the through hole 84 but gradually increases as the distance from the through hole 84 increases. In addition, the front ridgeline part 86 may be formed with the slope, and may be formed with the curved surface. As described above, since the front ridge line portion 86 is inclined, the movement of the shoulder 8 in the traveling direction 100 is not easily inhibited by the inner corner portion 90.

Furthermore, it is desirable that the size D ₁ in the depth direction of the guide groove 87 from the rear end to the front end in the traveling direction 100 of the front ridge line portion 86 is larger than the depth D ₂ of the guide groove 87 (FIG. 4). In other words, the position in the depth direction of the guide groove 87 at the rear end in the traveling direction 100 of the front ridge line portion 86 and the position in the depth direction of the front guide groove 87 in the direction of travel 100 of the front ridge line portion 86 are guided. It is desirable that the distance is greater than the depth D ₂ of the groove 87. As a result, there is a front ridge line portion 86 (particularly, a portion indicated by an arrow 86a in FIG. 5) that is inclined forward from the front end of the guide groove 87 in the traveling direction 100. Therefore, the wire 50 passing through the front of the traveling direction 100 with respect to the guide groove 87 comes into contact with the front ridge line portion 86 provided with an inclination, so that the wire 50 is caught by the shoulder 8 and the feeding of the wire 50 is hindered. Can be prevented.

The rear ridge line part 88 has a function of forming a shape (for example, a curved surface shape) of the inner corner part 90 after joining by contacting with the base material after stirring. For this reason, the cross-sectional shape of the advancing direction 100 of the back ridgeline part 88 respond | corresponds with the cross-sectional shape of the advancing direction 100 of the inner corner part 90 after joining. In the present embodiment, the cross-sectional shape in the advancing direction 100 of the rear ridge line portion 88 is smooth so that a smooth curve connecting the first member 91 and the second member 92 is formed in the inner corner portion 90 after joining. It has become a mountain shape.

The front ridge line part 86 is set back from the inner corner part 90 rather than the rear ridge line part 88. The front ridge line portion 86 and the inner corner portion 90 are separated so that the inner corner portion 90 and the front ridge line portion 86 are not in contact with each other and the wire 50 can be introduced between the inner corner portion 90 and the guide groove 87. Yes. On the other hand, the rear ridge line part 88 has little or little separation distance between the inner corner part 90 and the rear ridge line part 88 so as to come into contact with the inner corner part 90 after stirring. As described above, since the front ridge line portion 86 is retracted from the inner corner portion 90 rather than the rear ridge line portion 88, the wire 50 supplied to the bonded portion may come into contact with the front ridge line portion 86 in the process. Avoided.

The base 7 and the shoulder 8 configured as described above are configured such that the base plate portion 81 of the shoulder 8 is fitted into the recess 73 of the base 7, and bolts are screwed into the mounting

holes

83 and 75 that are aligned in the axial direction. , An integrated shoulder block 3 is obtained. In the shoulder block 3, the through hole 84 of the shoulder 8 and the through hole 74 of the base 7 communicate with each other to form one insertion hole 31. The insertion hole 31 has a large-diameter portion 31a including an inlet on the base 7 side, a small-diameter portion 31c including an outlet on the shoulder 8, and a tapered portion 31b that smoothly connects the large-diameter portion 31a and the small-diameter portion 31c. is doing. The diameter of the small diameter portion 31 c is slightly larger than the diameter of the tip of the stirring pin 21. The inclination of the taper part 31b from the axial direction coincides with the inclination of the taper part formed on the stirring pin 21 of the rotary tool 2. When the rotary tool 2 is inserted into the insertion hole 31 of the shoulder block 3, the taper part 31b of the insertion hole 31 and the taper part of the stirring pin are brought into contact with each other, so that the shoulder block 3 and the rotary tool 2 are relatively positioned. Is done. In the rotary tool 2 and the shoulder block 3 positioned as described above, the stirring pin 21 at the tip of the rotary tool 2 is in a state protruding from the shoulder block 3 by a predetermined length. A cylindrical collar 48 is provided between the large diameter portion 31 a of the shoulder block 3 and the rotary tool 2. The collar 48 is a member provided for stably rotating the rotary tool 2 with respect to the shoulder block 3.

Here, a method for manufacturing a metal structure using the friction stir welding apparatus 1 having the above configuration will be described. FIG. 9 is a flowchart showing a method for manufacturing a metal structure using a friction stir welding apparatus.

As shown in FIG. 9, first, the first member 91 and the second member 92 are abutted in an L shape or a T shape as shown in FIG. 1, and a jig 95 that functions as a backing member is used. Hold (step S1). The first member 91 and the second member 92 that are abutted with each other form an inner corner 90 that is a joined portion.

Next, the shoulder block 3 is disposed in the inner corner 90 (step S2). Here, the shoulder block 3 is disposed at the inner corner 90 so that the shoulder surfaces 85, 85 of the shoulder block 3 come into contact with the first member 91 and the second member 92. In the shoulder block 3 arranged in the inner corner 90 in this way, the front ridge line portion 86 and the rear ridge line portion 88 of the shoulder 8 are arranged along the butt line of the inner corner portion 90 and face the butt line. ing.

Subsequently, the stirring pin 21 of the rotary tool 2 is inserted into the insertion hole 31 of the shoulder block 3 (step S3). Here, the stirring pin 21 is inserted into the insertion hole 31 until the tip thereof abuts on the inner corner portion 90. Then, the tip of the stirring pin 21 is pushed into the base material of the joined portion while rotating the stirring pin 21 until the tapered portion of the stirring pin 21 contacts the tapered portion 31b of the shoulder block 3. Thereby, the front-end | tip of the stirring pin 21 is press-fitted in the base material of a to-be-joined part. In order to reduce the resistance when the stirring pin 21 is press-fitted into the base material of the joined portion, a pilot hole can be provided in the inner corner portion 90.

Subsequently, while the stirring pin 21 is rotated, the stirring pin 21 and the shoulder block 3 are moved forward in the advancing direction 100 along the abutting line of the inner corner portion 90 to frictionally stir the welded portion and the wire 50 ( Step S5). At the same time or earlier, the wire feeding device 44 feeds the wire 50 to the joined portion in accordance with the moving speed (that is, the joining speed) of the stirring pin 21 and the shoulder block 3. The wire 50 is heated by the wire heating device 45 in the process of being fed to the bonded portion. That is, the preheated wire 50 is supplied to the joined portion (step S4).

Friction heat is given to the base material (the first member 91 and the second member 92) of the joined portion and the wire 50 fed to the joined portion by the rotating stirring pin 21. The base material of the bonded portion and the wire 50 softened by the frictional heat are agitated and plastically flow. Due to the relative movement of the stirring pin 21 in the traveling direction 100, plasticization occurs sequentially at the inner corner 90, and the inner corner 90 of the first member 91 and the second member 92 is solid-phase bonded.

In the process described above, a metal structure in which the first member 91 and the second member 92 are friction stir welded is manufactured. And in the said manufacturing method, the wire stirred with the base material of a to-be-joined part is heated previously. Therefore, it becomes possible to eliminate the insufficient softening of the base material and the wire 50 of the joined part due to the lack of heat input to the base material and the wire 50 of the joined part. Thus, since the wire 50 is supplied to the joined portion so that the base material of the joined portion and the wire 50 are well stirred, the joined portion of the metal structure joined by this friction stir welding It is possible to prevent defects from occurring on the surface. That is, the joining state and joining strength of the friction stir welding part can be stabilized. Furthermore, since the amount of heat input necessary for softening the wire 50 is reduced by preheating the wire 50, the bonding speed can be improved.

Although the preferred embodiment of the present invention has been described above, the configuration of the friction stir welding apparatus 1 can be changed as follows, for example.

For example, the wire heating device 45 of the friction stir welding apparatus 1 according to the above-described embodiment is configured to heat the wire 50 by energizing the wire 50. However, the heating method of the wire heating device 45 is not limited to this. For example, the wire heating device 45 may be configured to heat the wire 50 by electromagnetic induction or a heating element.

FIG. 10 is a diagram illustrating a schematic configuration of the friction stir welding apparatus 1 including the wire heating device 45 according to the first modification. As shown in FIG. 10, the wire heating device 45 includes, for example, a heater 61 including a coil, a temperature sensor 62 that detects the temperature of the wire 50 heated by the heater 61, and a temperature controller 63. ing. The temperature controller 63 is configured to adjust the current flowing through the coil of the heater 61 based on the temperature of the wire 50 detected by the temperature sensor 62. When a current flows through the coil of the heater 61, magnetic lines of force that change in direction and strength are generated around the coil, and an eddy current flows in the wire 50 due to the influence of the lines of magnetic force. When a current flows through the wire 50, heat is generated by the resistance of the wire 50, and the wire 50 self-heats. In this way, the wire 50 is heated by electromagnetic induction. The heater 61 may include a coil as a heating element. In this case, when a current flows through the coil of the heater 61, the heater 61 generates heat, and the wire 50 is heated by this heat.

Further, for example, the friction stir welding apparatus 1 according to the embodiment includes the wire feeding device 44 and actively supplies the wire 50 to the joined portion. According to this configuration, the heated wire can be continuously supplied to the bonded portion. However, the friction stir welding apparatus 1 may not include the wire feeding device 44. In this case, the wire 50 is supplied to the joined portion following the movement of the rotary tool 2 and the shoulder block 3 in the traveling direction 100.

DESCRIPTION OF SYMBOLS 1 Friction stir welding apparatus 2 Rotating tool 21 Stirring pin 3 Shoulder block 31 Insertion hole 7 Base 71 Mounting surface 72 Guide surface 73 Recess 74 Through hole 75 Mounting hole 8 Shoulder 81 Substrate part 82 Projection part 83 Mounting hole 84 Through hole 85 Shoulder surface 86 Front ridge line portion 87 Guide groove 88 Rear ridge line portion 41 Rotation drive device 42 Press device 43 Movement device 44 Wire feeding device 45 Wire heating device 46 Control device 50 Wire 90 Inner corner portion 91 First member 92 Second member

Claims

A friction stir welding apparatus that performs friction stir welding with respect to an inner corner formed by two metal members abutted against each other,
A rotating tool having a stirring pin at the tip;
A shoulder inserted through the rotary tool and abutting against the two metal members;
A rotation drive device for rotating the rotating tool around an axis;
A pressing device that presses the rotating tool and shoulder against the inner corner; and
A moving device for moving the rotating tool and the shoulder in the traveling direction along the inner corner;
A friction stir welding apparatus comprising: a wire heating device that heats a wire that is frictionally stirred together with the two metal members by the stirring pin.
A wire feeding device for feeding the wire to the bonded portion of the two metal members;
The friction stir welding apparatus according to claim 1, wherein the wire heating apparatus is configured to heat the wire fed to the joined portion by the wire feeding apparatus.
The friction stir welding apparatus according to claim 1 or 2, wherein the wire heating device is configured to heat the wire by energizing the wire.
The friction stir welding apparatus according to claim 1 or 2, wherein the wire heating device is configured to heat the wire by electromagnetic induction.
The friction stir welding apparatus according to claim 1 or 2, wherein the wire heating device is configured to heat the wire by a heating element.
The shoulder is
An insertion hole through which the rotating tool is inserted;
Two shoulder surfaces provided on both sides in a direction substantially perpendicular to the traveling direction with the opening of the insertion hole interposed therebetween, and forming an angle corresponding to the angle of the inner corner formed by the two metal members; ,
2. A guide groove for the wire, which is provided in a front ridge line portion where the two shoulder surfaces intersect with each other in front of the opening direction of the insertion hole and extends in parallel with the traveling direction. The friction stir welding apparatus according to any one of claims 1 to 5.
The front ridge line part is retreated from the inner corner part than the rear ridge line part where the two shoulder surfaces intersect at the rear in the traveling direction from the opening part of the insertion hole,
The friction stir welding apparatus according to claim 6, wherein the cross-sectional shape in the traveling direction of the rear ridge line portion has a shape corresponding to the cross-sectional shape in the traveling direction of the inner corner portion after joining.
The friction stir welding apparatus according to claim 6 or 7, wherein the front ridge line part is inclined so as to be separated from the inner corner part toward the front in the traveling direction.
The friction stir welding apparatus according to claim 8, wherein a size of the guide groove in a depth direction from one end of the front ridge line portion to the other end of the travel direction is larger than a depth of the guide groove. .
The friction stir welding apparatus according to any one of claims 6 to 9, further comprising a base to which the shoulder is detachably attached and has a hole continuous with the insertion hole of the shoulder.
Butting the first metal member and the second metal member into an L shape or a T shape,
Heating the wire;
Supplying the heated wire to an inner corner formed by the butted first metal member and the second metal member;
A method of manufacturing a metal structure, comprising: press-fitting a stirring pin that rotates into the inner corner portion, and friction stir welding the first metal member, the second metal member, and the wire.
The method for manufacturing a metal structure according to claim 11, wherein heating the wire includes heating the wire by energizing the wire.
The method for manufacturing a metal structure according to claim 11, wherein heating the wire includes heating the wire by electromagnetic induction.
The method for manufacturing a metal structure according to claim 11, wherein heating the wire includes heating the wire by a heating element.
The first metal member is made of an A2000 series aluminum alloy,
The second metal member is made of an A7000 series aluminum alloy,
The method for manufacturing a metal structure according to any one of claims 11 to 14, wherein the wire is made of an A2000 series aluminum alloy or an A7000 series aluminum alloy.